Synthesis of new tricyclic 5,6-dihydro-4H-benzo[b][1,2,4]triazolo[1,5-d][1,4]diazepine derivatives by [3⁺ + 2]-cycloaddition/rearrangement reactions

• Lin-bo Luan,
• Zi-jie Song,
• Zhi-ming Li and
• Quan-rui Wang

Beilstein J. Org. Chem. 2018, 14, 1826–1833, doi:10.3762/bjoc.14.155

• occurred smoothly to yield the dihydroquinolinones 5, which were then converted to 1-acetyl-2,3-dihydroquinolin-4(1H)-ones 6 by reaction with acetyl chloride in 36–56% overall yields (Scheme 1, see Supporting Information File 1 for details). The phenylhydrazones 7 were readily acquired by condensation of

• neutral tricyclic heterocycles. To this end, the phenylhydrazones 7 were replaced by the ethoxycarbonylhydrazone 11, in which the ethoxycarbonyl group was hoped to be removable by hydrolysis [34]. As presented in Scheme 4, ethyl carbazate was used to prepare the hydrazone 11 by condensation with 2,3

• -dihydro-4(1H)-quinolone 6a [46]. However, it was odd that the oxidation using the hypervalent iodine(III) reagent PhI(OAc)2 as described for phenylhydrazones 7 failed to produce the expected α-acetoxy-ethoxycarbonyl compound 12. Instead, the hydrazone 11 remained intact and was recovered. Therefore, we

Aminofluorination of 2-alkynylanilines: a Au-catalyzed entry to fluorinated indoles

• Antonio Arcadi,
• Emanuela Pietropaolo,
• Antonello Alvino and
• Véronique Michelet

Beilstein J. Org. Chem. 2014, 10, 449–458, doi:10.3762/bjoc.10.42

• and alkynyl phenylhydrazones, respectively. Propargyl amidines were converted into 5-fluoromethylimidazoles in the presence of Selectfluor under gold(I) catalysis [34][35][36] through a cascade cyclization/fluorination process [37]. Following our previous work on gold catalysts (Scheme 1) [38], we

Derivatives of phenyl tribromomethyl sulfone as novel compounds with potential pesticidal activity

• Krzysztof M. Borys,
• Maciej D. Korzyński and
• Zbigniew Ochal

Beilstein J. Org. Chem. 2012, 8, 259–265, doi:10.3762/bjoc.8.27

• . Keywords: 2-nitroaniline derivatives; phenylhydrazones; pesticides; SNAr reaction; tribromomethyl sulfone derivatives; Introduction The rapid growth of the world population results in a continous increase in the demand for food. At the same time, about 35% of the global crops around the world are being

• molecules remained to be synthesized: Phenylhydrazones and benzimidazoles. The acid-catalyzed reaction of phenylhydrazine derivative 7b with aldehydes or ketones (Scheme 5) afforded a series of phenylhydrazones possessing various substituents (Table 2; see Supporting Information File 1 for further details

• of phenylhydrazones 8a–8l. Products of the nitro group reduction of sulfone 7a. Synthesis of benzimidazole derivatives 11a–11g. Preparation and further transformation of 2-mercaptobenzimidazole 11h. Derivatives of 2-nitroaniline, 2-nitrophenylhydrazine and diphenyl ether. 2-Nitro-4